Does the open area of my window make a difference?

[Fodder]

So I was wondering whether the amount of open area of my window would make a difference in how much cold air gets in?

Please tell me if I should provide more information, I'm pretty new to this.

 

[Drakkith]

Absolutely. If your window is 3 feet wide and you open it by 2 inches, you won't let in nearly as much air as you would if you opened it by 2 feet.

 

[phinds]

So I was wondering whether the amount of open area of my window would make a difference in how much cold air gets in?

Please tell me if I should provide more information, I'm pretty new to this.

Well, let's take extremes and see what YOU think. Two scenarios: (1) You have a REALLY small opening. Second, you have a REALLY big window and it is all the way open.

What you do you expect to happen?

 

[DoItForYourself]

Hi and welcome to PF,

As long as you have another window/s open and there is air flow in the house/room, the flow of air into the house/room is approximately proportional to the surface area of the open window (u=QA, u: velocity of air, Q: volumetric flow of air, A: surface area of the open window.

If the other windows and doors are all closed, then some warm air from inside the house will go out of the window, but again the flow of air into the house/room will be proportional to the surface area of the opening.

 

[Fodder]

My window looks like this, and the thing is I was wondering if I opened the one on the right to the max would it make a difference from opening it to the one on the middle

 

[Fodder]

Well, let's take extremes and see what YOU think. Two scenarios: (1) You have a REALLY small opening. Second, you have a REALLY big window and it is all the way open.

What you do you expect to happen?

I would most likely choose the second one, but would it make a difference if my window was half open or fully open? like does it make the room colder if I choose the fully open one? ( Please watch the picture for reference, also thanks for commenting I thought nobody would answer this)

 

[DoItForYourself]

In this case, it has to do with the open surface area and the direction of the air.

Generally, in the middle window, the volumetric flow will be less (if you have the same opening area with the third window), because the molecules of air will be scattered in a bigger extent and most of them will return outside the house.

Anyway, if you let the window open for much time, the room temperature will be equal to T_out. However, the faster way to reach T_out is the third window (this way of opening).

 

[Fodder]

In this case, it has to do with the open surface area and the direction of the air.

Generally, in the middle window, the volumetric flow will be less (if you have the same opening area with the third window), because the molecules of air will be scattered in a bigger extent and most of them will return outside the house.

Anyway, if you let the window open for much time, the room temperature will be equal to T_out. However, the faster way to reach T_out is the third window (this way of opening).

Now this makes sense to me, I suck at physics and that's why I came here to ask this question. But is there any formula/theory for the last part "
if you let the window open for much time, the room temperature will be equal to Tout. However, the faster way to reach Tout is the third window (this way of opening).".

 

[DoItForYourself]

Now this makes sense to me, I suck at physics and that's why I came here to ask this question. But is there any formula/theory for the last part "
if you let the window open for much time, the room temperature will be equal to Tout. However, the faster way to reach Tout is the third window (this way of opening).".

This specific phenomenon can be explained/analysed with the help of thermodynamics (fluid dynamics and heat transfer phenomena).

Computational Fluid Dynamics (CFD) is a very interesting field of thermodynamics. For example, you can simulate this situation in COMSOL Multiphysics, drawing a house exactly and setting which doors/windows are open and which are closed and you will get the temperature distribution in the house.

 

[Fodder]

This specific phenomenon can be explained/analysed with the help of thermodynamics (fluid dynamics and heat transfer phenomena).

Computational Fluid Dynamics (CFD) is a very interesting field of thermodynamics. For example, you can simulate this situation in COMSOL Multiphysics, drawing a house exactly and setting which doors/windows are open and which are closed and you will get the temperature distribution in the house.

Right, thanks for answering, I will read a bit about fluid dynamics.